Indicates important notes at the bottom of the page.

Weapons

1 (5 ★)
2 (4 ★)
3 (5 ★)
4 (4 ★) [R3]

Artifact Sets

1
2
+20% ER set (2)
+20% HP set (2)
+15% Hydro DMG Bonus set (2)
[Choose Two]
3

Artifact Stats

Main Stats

Sands Energy Recharge / HP%
Goblet Hydro DMG / HP%
Circlet CRIT Rate / CRIT DMG / HP%

Substats

1 Energy Recharge
2 HP%
CRIT Rate / CRIT DMG
3 Flat HP

Talents

1 Burst
2 Skill
3 Normal Attack

Notes

Yelan's primary role is as an off-field Hydro DPS who can also enable reactions thanks to her elemental application. Similarly to Xingqiu, her exquisite throws from Burst require your character to perform the Normal Attack action.

Big thanks to Vladone ツ#9281 for helping out

Regarding Weapon Choices:

Elegy for the End: This weapon is not ideal for Yelan's personal damage so should only be used in teams which can utilise the buff well.
Aqua Simulacra: Still the best option for personal damage even at high Energy Recharge requirements, but may be unfeasible to run in some teams as the Energy Recharge requirement can become very difficult to reach without an Energy Recharge weapon.
Sacrificial Bow: This ideally needs to be at refinement [R3-R5] to function properly in most Yelan teams rotations without desyncing the rotation and extending her field time.

Regarding Artifact Choices:

It's never recommended to run more than 2 HP% Main Stat artifacts at a time.

Sets

Marechaussee Hunter (4): This set should only be used for on-field Yelan with Furina, but in such cases it is the strongest set option.

Main Stats

HP%: Hydro DMG% should be used by default. In teams with significant DMG% buffing or with weapons which provide a lot of DMG%, HP% goblet can be competitive.

Substats

Energy Recharge: Prioritize until requirements are met.

Regarding Talent Choices:

Normal Attack: Level this up only if you want to constantly use her Breakthrough Barbs.